Dead man’s fingers – Alcyonium digitatum

During March, I spent two weeks filming in the clear waters of Loch Carron.

When I set out, I didn’t know what I was going to find at this time of year. I decided to go, see what turned up, and let my curiosity do the rest.

I started on the flame shell reef but found it to be barren of life, dull brown in colour, and devoid of the colourful seaweed that shelters summer residents. I tried a night dive but the results were no different.

As I swam to the flame shell reef every day, I passed close to a vertical wall. Here, dead man’s fingers (DMFs), one of the UK’s most common soft corals, fed with their polyps out in the tide. They varied in colour from white to deep orange and looked beautiful against the emerald green water.

On closer inspection I found most of the life I’d expected to see on the flame shell reef in amongst the DMFs. At this time of year this is clearly the preferred habitat. Most of the animals were small and so to capture macro images, I needed to keep my camera rock solid. This restricted me to the bottom metre of the wall where I could work off a tripod on the seabed.

After the first week I had filmed some interesting life like the tiny amphipod Iphimedia obesa but the animal that interested me most remained tantalisingly out of reach. Tritonia hombergii (DMF sea slug) was breeding, feeding and teasing me, high up on the wall, beyond the range of my tripod. The few shots I captured were static as Tritonia live out their lives in a time frame that is much slower than ours.

Back home, reviewing my footage, I decided that to complete this story, I needed to film Tritonia in a different location (not a wall) and use time-lapse to speed up their behaviour.

I talked to Sue Scott, George Brown and Mark Skea and it became clear that a few hundred metres from Strome, Conservation Bay could offer what I needed. Here DMFs populate the seabed in great numbers and Mark had seen Tritonia amongst them the week after I had dived at Strome.

So it was back to Loch Carron again. A scottish diver called Willie Stuart introduced me to Conservation Bay and the Tritonia. They were doing everything I had hoped for – but very slowly. It took a full week diving twice a day but time-lapse has enabled me to capture how they move and feed and how DMFs react to them.

So now I have a story that looks at a typical day in the life of the UK’s most common soft coral. Follow the video link and have a look at them, the habitat they create, and the animals that depend upon it.

After watching this I hope you’ll agree that the name Dead Man’s Finger doesn’t really capture the magic of this animal, and that we should be very proud of the amazing coral reefs we have all around our UK shores.

Special thanks to Sue Scott for all her help.

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Images and words by Andy